Is efficiency sente?

SmoothOper · #1

I have been trying to grasp the theory behind Lee Changho's style. From what I can glean from the internet thus far, is that he preferred solid thick but efficient openings and relied on late mid-game and yose moves, and is generally uninterested in moyos, sente plays(with the exception of pure profit moves), running groups and or attacking groups.

I guess I am wondering how you would recognize this style of play, and what would happen if two Buddhas were to play each other. Is efficiency sente?

Joaz Banbeck · #2

Efficiency is definitely not sente. A sente move is simply one that forces an opponent to respond. In some cases, it may be an efficient use of stones. In others, It can be very inefficient.

An example:

We start with a symetrical position:

Click Here To Show Diagram Code: [go]$$Bc $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . X . O . . . . . . . . | $$| . . . X . . . . . . . . . . . O . . . | $$| . . . . . . . . X . O . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$------------------------------[/go]

Black moves...

Click Here To Show Diagram Code: [go]$$Bc $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . X . O . . . . . . . . | $$| . . . X . . . . . . 2 1 . . . O . . . | $$| . . . . . . . . X . O . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$------------------------------[/go]

Black's move is sente. White must respond. But after the exchange, white's stones have no weaknesses, whereas black's do. White's stones are more efficient.

Black 1 was inefficient, but sente.

Many beginners have this problem. They play moves that are sente, but which are aji keshi.

SmoothOper · #3

Joaz Banbeck wrote:

Efficiency is definitely not sente. A sente move is simply one that forces an opponet to respond. In some cases, it may be an efficient use of stones. In others, It can be very inefficient.

An example:

Click Here To Show Diagram Code: [go]$$Bc $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . X . O . . . . . . . . | $$| . . . X . . . . . 1 2 . . . . O . . . | $$| . . . . . . . . X . O . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$------------------------------[/go]

Black's move is sente. White must respond. But after the exchange, white's stones have no weaknesses, whereas black's do. White's stones are more efficient.

Black 1 was inefficient, but sente.

What I am suggesting is that if a player makes a move that produces an efficient shape, one must respond to the efficient move as if it were a threat.

Joaz Banbeck · #4

SmoothOper wrote:

...if a player makes a move that produces an efficient shape, one must respond to the efficient move as if it were a threat.

Not at all. One could make a very efficient defensive move.

Consider this game:

Click Here To Show Diagram Code: [go]$$c $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . X . . . . . , . . . . . O . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . 6 a . . | $$ | . . . X . . . . . , . . . . . O 5 . . | $$ | . . . . . . . . . . . 2 . 1 0 4 3 . . | $$ | . . . . . . . . . . . . . . 8 7 9 . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

This is a common joseki. White is threatening 'a'. So black plays a very efficient move. But it is an efficient defensive move.

Click Here To Show Diagram Code: [go]$$c $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . X . . . . . , . . . . . O . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . 1 . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . . X . . . . . , . . . . . O X . . | $$ | . . . . . . . . . . . O . X O O X . . | $$ | . . . . . . . . . . . . . . O X X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

According to Daily Joseki, over 75% of pros will tenuki as white.

skydyr · #5

SmoothOper wrote:

Joaz Banbeck wrote:

Efficiency is definitely not sente. A sente move is simply one that forces an opponet to respond. In some cases, it may be an efficient use of stones. In others, It can be very inefficient.

An example:

Click Here To Show Diagram Code: [go]$$Bc $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . X . O . . . . . . . . | $$| . . . X . . . . . 1 2 . . . . O . . . | $$| . . . . . . . . X . O . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$------------------------------[/go]

Black's move is sente. White must respond. But after the exchange, white's stones have no weaknesses, whereas black's do. White's stones are more efficient.

Black 1 was inefficient, but sente.

What I am suggesting is that if a player makes a move that produces an efficient shape, one must respond to the efficient move as if it were a threat.

I think an efficient move demands an equally or more efficient response, but that's not really sente as such, since it could occur anywhere. Perhaps thinking of it in terms of miai is a better framework?

Tryss · #6

skydyr wrote:

I think an efficient move demands an equally or more efficient response, but that's not really sente as such, since it could occur anywhere. Perhaps thinking of it in terms of miai is a better framework?

Sure, but you always want to play more efficiently than your opponent, so it's like saying "if my opponent play slack moves, I can play moves just a little better than him and still win"

RobertJasiek · #7

There is no need to reinvent the wheel. My book definition of efficiency is "the optimal compromise between safety and speed of local movement".

Uberdude · #8

RobertJasiek wrote:

There is no need to reinvent the wheel. My book definition of efficiency is "the optimal compromise between safety and speed of local movement".

You do need to reinvent the wheel if the previous one is square. Your definition misses the key point of efficiency (in both general English and Go usage) in that you are achieving as much as possible using limited resources, i.e. each stone is working well and isn't wasted.

Your definition sounds as though you are trying to use it to describe somewhere between fast-paced yet thin and leaving weakness play, and more solid but slower development. But there is no unique optimum on this scale, often both can be good ways to play and it is an orthogonal concept to efficiency: Takemiya can make a big loose moyo and Kitani some small solid territory and both be efficient.

gogameguru · #9

RobertJasiek wrote:

There is no need to reinvent the wheel. My book definition of efficiency is "the optimal compromise between safety and speed of local movement".

Like Uberdude, I also find that definition surprising and his definition seems to be better. To start with, why did you decide it was necessary to include the word 'local' in the definition you gave in your book?

Joaz Banbeck · **#10**

[admin]

Gentlemen,

This has the seeds of a thread hijacking. Please keep on topic.
And please remember that we have a forum for advertising books.

Thanks

JB

[/admin]

gogameguru · **#11**

Sorry. I think Andrew and I were both legitimately questioning what seemed to be an unusual definition of efficiency (in a topic about efficiency).

I have to admit, I've been ignoring most of those other long discussions recently, so I'm not sure if there's some new forum policy I don't know about here.

EDIT: Now that I've thought about it a bit, I think I understand your point about how the general pattern of things has gone in the past...

And back on topic, sente can be both efficient or inefficient. It's something of an unrelated concept to efficiency, in my mind anyway.

tapir · **#12**

Joaz Banbeck wrote:

Click Here To Show Diagram Code: [go]$$Bc $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . X . O . . . . . . . . | $$| . . . X . . . . . . 2 1 . . . O . . . | $$| . . . . . . . . X . O . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$------------------------------[/go]

Black's move is sente. White must respond. But after the exchange, white's stones have no weaknesses, whereas black's do. White's stones are more efficient.

Black 1 was inefficient, but sente.

Many beginners have this problem. They play moves that are sente, but which are aji keshi.

Whether a stone is inefficient rarely shows in a single move, efficiency is not a property of single stones but of the work you get out of them during the course of the game. If Black gets to play O4 now or later the case that B1 is inefficient will be much less convincing, for then it will separate the White stones. Also moves akin to B1 occur regularly when a single fourth line stone is capped as below. Peeping from the side you don't reinforce or more general as a means to make your opponent heavy is a very common move.

Click Here To Show Diagram Code: [go]$$Bc B1 is efficient $$| . . . . . . . . . . . . . . . . . . . | $$| . . . X . . . . O . . . . . . . . . . | $$| . . . . . O . . . . . . . . . . . . . | $$| . . . X . 2 1 . X . . . . O . O . . . | $$| . . . . . O . . . . . . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$| . . . . . . . . . . . . . . . . . . . | $$------------------------------[/go]

Magicwand · **#13**

in korean word we call it 보리선수. (borisonsu)
sonsu is same as sente in japanese.
i have no idea where bori came from or what it means but two word combined will represent a sente that will help your opponent.
sente that is helping opponent has differnet point of view than sente that is inefficient.
i would like to call it helping opponent move. or call it borisunsu?

best example i can give you will be...below
that exchange looks innocent enough that many kyu players doesnt know that will hurt white by that exchange.
reason is that that exchange will fill the liberty and will create bad aji for white while black loses nothing.

Click Here To Show Diagram Code: [go]$$Wc $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . X . . . . . , . . . . . O . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . O 1 2 . | $$ | . . . X . . . . . , . . . . . O X . . | $$ | . . . . . . . . . . . O . X O O X . . | $$ | . . . . . . . . . . . . . . O X X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

SmoothOper · **#14**

Uberdude wrote:

RobertJasiek wrote:

There is no need to reinvent the wheel. My book definition of efficiency is "the optimal compromise between safety and speed of local movement".

You do need to reinvent the wheel if the previous one is square. Your definition misses the key point of efficiency (in both general English and Go usage) in that you are achieving as much as possible using limited resources, i.e. each stone is working well and isn't wasted.

Your definition sounds as though you are trying to use it to describe somewhere between fast-paced yet thin and leaving weakness play, and more solid but slower development. But there is no unique optimum on this scale, often both can be good ways to play and it is an orthogonal concept to efficiency: Takemiya can make a big loose moyo and Kitani some small solid territory and both be efficient.

Uberdude there is no need to compromise your beliefs in this case.

I think there are several possible resources to consider 1) Stones 2) mental ability 3) time.

RobertJasiek · **#15**

Uberdude wrote:

RobertJasiek wrote:

"the optimal compromise between safety and speed of local movement".

Your definition misses the key point of efficiency [...] in that you are achieving as much as possible using limited resources, i.e. each stone is working well and isn't wasted.

Efficiency is not about achieving as much as possible with the given stones. Instead, the go concept describing this is, what I call, 'best usage' (of one's stones). There are times when one's stones' best usage is their efficient placement (optimal compromise between safety and speed of local movement) and other times when one's stones' best usage is their safe (e.g., honte) placement (e.g., when one defends one's shape against possible later ko threat material).

The property "each stone is working well and isn't wasted" is a property of the strategic concepts 'best usage', 'efficiency' and 'haengma'. As a property of efficiency, it is a local property; as a property of haengma, it is a local to global property; as a property of best usage, it is an all-inclusive property, which in particular summarises inhowfar / how well efficiency and haengma are achieved.

Quote:

Your definition sounds as though you are trying to use it to describe somewhere between fast-paced yet thin and leaving weakness play, and more solid but slower development.

Yes.

Quote:

But there is no unique optimum on this scale,

Exactly. That's why my definition speaks of compromise.

Quote:

Takemiya can make a big loose moyo and Kitani some small solid territory and both be efficient.

Exactly. Efficiency is a strategic concept without absolute quality. Values of efficiency are assumed, at particular moments of the game / a sequence, in contexts of positional context, playing style etc. This context-embedding is not stated explicitly by my definition, and further research should be made to provide explicit embedding of such context. My definition is a working definition to identify the aspects of efficiency that can already be identified well. I encourage everybody to refine the definition, however, it must not be confused with haengma or best usage.

gogameguru wrote:

Like Uberdude, I also find that definition surprising

It has surprised also me because

1) it is surprisingly simple when seeking a balance between safety and movement speed,

2) it avoids improper confusion with other strategic concepts (i.e., efficiency is something that can be studied and, in some respects, expressed as values such as 'territory efficiency' without having to determine the ultimate winning move, the haengma's possibly global scale and the best usage's broader goals).

Quote:

and his definition seems to be better.

Uberdude's definition is not better for the reasons stated above. In particular, he confuses efficiency with or with aspects of haengma and best usage. This makes his definition mightier and so "more attractive" at first glance. It would be even mightier and yet more "attractive" to say "most efficient for a player is what leads to his best score at the game end". I dislike such overkills. Strategic concepts must have practical meaning. My definition has practical meaning: it is so practical that already important aspects of it can be expressed by values. Uberdude's definition is not practical because it wants to assess too much together including haengma and best usage.

Quote:

To start with,

If you have further objections, please state them! Only by discussing all we can find out or verify the best possible definition or description of the concept.

Quote:

why did you decide it was necessary to include the word 'local' in the definition you gave in your book?

Because efficiency is best understood as a local concept. If relative best relation and placement at a global scale is the issue, then the concepts to be considered are called 'haengma' and 'best usage'. Suppose you would want to exclude the 'local' condition from efficiency, then which strategic concept at all and instead do you still have for studying local, in some sense optimal stone development? Efficiency is the concept on the local scale. There is no need to remove this great property from the concept, quite like you do not remove "local" when considering "currently surrounded safe territory of a group". There are concepts for local considerations (territory) and concepts for global considerations (influence, implication of potential future territory on the global scale). Similarly, there is local optimal stone development (efficiency, short time scale) and there is global optimal stone development (haengma for asssing what is or will be in a short time scale; best usage for considering development over the time of a whole game's progress).

***

Joaz, IMO, a factual discussion about strategic concepts and references to (book or other) sources do not need an admin hint.

daal · **#16**

Robert, the word efficient already has a meaning, and while wordings may differ, they all basically amount to: "performing or functioning in the best possible manner with the least waste of time and effort" (Dictionary.com).
Reinventing the wheel would be to replace this good word with something else, such as "best usage."

golem7 · **#17**

I don't think there is a need to redefine efficiency as a local concept. It works both on a local and global scale. The introduction of "best usage" feels forced, it's just another description of efficiency. You don't really need seperate terms for that.
I suppose everyone remembers the following diagram. At least that's how I as a beginner first came into contact with the concept of efficiency in go. It includes both local and global considerations.

Click Here To Show Diagram Code: [go]$$c The first 10 moves... $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . X . . . | $$ | . . . O . . . . . , . . . . . X . . . | $$ | . . . . . . . . . . . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . X X . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . O . . . . . O . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Mef · **#18**

Magicwand wrote:

in korean word we call it 보리선수. (borisonsu)
sonsu is same as sente in japanese.
i have no idea where bori came from or what it means but two word combined will represent a sente that will help your opponent.
sente that is helping opponent has differnet point of view than sente that is inefficient.
i would like to call it helping opponent move. or call it borisunsu?

In English this is usually called a "thank you move" as in, you make this move and your opponent should be grateful that you made it (and say "thank you").

lovelove · **#19**

Mef wrote:

Magicwand wrote:

in korean word we call it 보리선수. (borisonsu)
sonsu is same as sente in japanese.
i have no idea where bori came from or what it means but two word combined will represent a sente that will help your opponent.
sente that is helping opponent has differnet point of view than sente that is inefficient.
i would like to call it helping opponent move. or call it borisunsu?

In English this is usually called a "thank you move" as in, you make this move and your opponent should be grateful that you made it (and say "thank you").

Thank you move is 이적수 (利敵手) in Korean. 보리선수 should be aji-keshi from Magicwand's diagram.

Uberdude · **#20**

RobertJasiek wrote:

Efficiency is not about achieving as much as possible with the given stones. Instead, the go concept describing this is, what I call, 'best usage' (of one's stones).

Just you then. :roll:

Is efficiency sente?

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